Retinal implants are at a bit of a turning point, with the first major successes just now being seen. In the past decade, we've seen some minor successes with what are essentially video cameras
plugged into the brain, but the level of detail available in those is limited to roughly "is it bigger than a breadbox" territory. The most impressive bionic eye at the moment, at least to me, was developed by researchers
at University Eye Clinic in Tübingen, Germany, and implanted in 11 people with varying--but undeniably impressive--success.
This retinal implant is unusual in that it relies on a chip that's implanted into the patient's own eyes, doing the job the retina normally would: converting light that hits the eye into electrical impulses, and feeding those impulses into the optic nerve. A formerly blind Finnish man outfitted with the new chip was able to see letters, read a clock, and even catch the tricky researchers when they misspelled his name.
So that's the present (if by "present" we are loosely including anything that has been demonstrated, even if it's still years away from wide adoption, which I am). The future, however, looks absolutely insane for bionic eyes--check out the "runners-up" section below.
It's not currently being used by any patients; the researchers are working on higher-resolution models with power sources implanted beneath the skin. But with one working prototype under their belt, you can bet this one isn't too far off.
A European-Commission-funded group is working on a retinal implant that relies on nano-sized diamonds, Patrick Degenaar is working on LED-driven eyes
, Oxford University is working on a pair of sight-restoring glasses
, and a University of Oregon professor is working on an optic implant that relies on tiny fractals